A diverse group of 11 NIH funded investigators, within the Johns Hopkins University Krieger School of Arts and Sciences, Whiting School of Engineering, and the School of Medicine request funds to purchase a Chameleon ULTRA II Ti:Sapphire multiphoton laser;a Zeiss environmental incubator (for modulating temperature, humidity, and CO2);and NLO hardware necessary to integrate the new laser onto an existing LSM 510 VIS system equipped with a Confocor-3 Fluorescence Correlation Spectroscopy module. The resulting configuration will significantly upgrade the FCS capability of the Confocor-3;and add a new live cell/deep tissue imaging resource that is presently absent from the Homewood campus. It will be a boon to multiple ongoing research programs within biology, psychology, biophysics, engineering, and the newly expanded neuroscience presence on Homewood. The instrument is situated in the Johns Hopkins Integrated Imaging Center (IIC, http://www.jhu.edu/iic), a core facility associated with the Institute of NanoBioTechnology (INBT, http://inbt.jhu.edu/index.php). The IIC is a Homewood campus/Hopkins-wide microscopy resource, jointly supported by the Krieger School of Arts and Sciences and the Whiting School of Engineering (see Lattman &Jones letters, page 2 of the appendix);and utilized regularly by multiple universities, schools, and departments comprising >80 laboratories and more than 250 users. Our investigators, all well funded through the NIH, work on a host of diverse basic cell biology and biomedical engineering related questions including, though not limited to: cell differentiation and gene regulation;Herpes virus assembly and maturation, membrane trafficking, mitochondrial fission, membrane protein folding, organogenesis, and circadian rhythm neuronal circuitry. In the updated configuration, the LSM 510/Confocor 3 will afford our disparate group of investigators a broad range of basic/advanced in vivo and in vitro microscopy capabilities that are presently absent from the Hopkins Homewood campus. The new system will be incorporated into the IIC's existing, well established recharge system to ensure recovery of funds for supplies and maintenance;it will be made freely available to all interested users Hopkins- wide through our convenient web-scheduler;and it will be incorporated into the IIC's annual undergraduate/graduate course offerings. PUBLIC HEALTH RELEVANCE: Ti:Sapphire Laser upgrade to LSM 510/Confocor-3 Fluorescence Correlation Spectroscopy System will be used for monitoring the interactions of fluorescent biomolecules and biomacromolecular complexes in their native sub-cellular environments;and for deep tissue and live imaging experiments.